This invention relates to a process and, in particular, to a process for preparing polymeric ketoximes and aldoximes.
Polymeric ketoximes and aldoximes are known. These materials may be characterized as polymers comprising recurring units which comprise an oxime moiety of the formula ##STR1## wherein R is hydrogen, alkyl, or aryl, including substituted alkyl or aryl. Generally, such polymers have heretofore been prepared by polymerizing a monomer containing a reactive keto or formyl group and reacting the resultant polymer, i.e., the keto or formyl groups in the resultant polymer, with hydroxylamine. High molecular weight polymeric oximes, e.g., polymeric oximes having a molecular weight of 50,000 or greater, normally have been prepared by this method.
The preparation of certain polymeric oximes by the method of polymerizing a monomeric oxime has been disclosed. A series of publications by Masuda et al. in Polymer Journal, Vol. 11, No. 8, pp. 641-649 (1979); Vol. 11, No. 3, pp. 213-218 (1979); Vol. 10, No. 4, pp. 397-402 (1978); and in publications referenced therein, discloses the polymerization of acrolein oxime in organic solvent systems employing various means of initiating the polymerization reaction. The molecular weights of the polymers obtained were reported to be very low, generally about 1000-3000. The copolymerization of p-vinylacetophenone oxime with styrene and methylmethacrylate and p-isopropenylacetophenone oxime with styrene using ethyl alcohol or alcohol-benzene as a solvent is reported by B. A. Zaitsev and G. A. Shtraikhman in Vysokomol. soyed., A 10: No. 2, 438-445, (1968), English translation at page 511. Molecular weights of the resultant polymers are not reported. U.S. Pat. No. 4,202,694, issued May 13, 1980 to L.D. Taylor, refers to certain unsuccessful attempts to prepare high molecular weight polymers by polymerization of monomeric oximes.